8.4 A 200 MHz, left-hand circularly polarized plane wave with an electric field modulus of 5 V/m is normally incident in air upon a dielectric medium with εr = 4 and occupies the region defined by z > 0. er (a) Write an expression for the electric field phasor of the incident wave, given that the field is a positive maximum at z = 0 and t = 0. (b) Calculate the reflection and transmission coefficients. Write expressions for the electric field phasors of the reflected wave, the transmitted wave, and the total field in the region z≤0. (d) Determine the percentages of the incident average power reflected by the boundary and transmitted into the second medium.